Conventionally, an electric motor with brushes has been known as a power source for in-vehicle equipment, and one example thereof is described Japanese Patent Application Laid-Open Publication No. 2010-57299. The electric motor described in Japanese Patent Application Laid-Open Publication No. 2010-57299 is used for a sunroof apparatus of a vehicle, and the electric motor is provided with an armature which is located inside a yoke having a bottomed cylindrical shape. The armature has an armature shaft, and the armature shaft is rotatably supported inside the yoke via shaft bearings. An armature core and a commutator are attached to the armature shaft. Furthermore, a plurality of armature coils are wound around the armature core, and the end portions of the armature coils are connected to the commutator. Furthermore, a brush holder is attached to an opening end of the yoke, and a pair of brushes is attached to the brush holder. The paired brushes make electrical contact with an outer periphery of the commutator. Furthermore, power supply terminals are connected to the paired brushes, and the power supply terminals are connected to connection members of a control board. The control board has a control circuit for controlling an electric current to be supplied to the commutator via the brushes.
On the other hand, a casing is fixed to the opening end of the yoke, and a worm wheel is provided in the casing and rotated integrally with an output shaft. An outer periphery of the worm wheel is formed with a gear. One end portion of the above-mentioned armature shaft is disposed inside the casing, and the outer periphery of this end portion of the armature shaft is formed with a worm. This worm is engaged with the gear formed on the outer periphery of the worm wheel. In addition, a grounding terminal serving as an earth terminal is formed on the casing, and by the grounding terminal, the control circuit of the control board is earthed (grounded) to the yoke so that the resistance of the control circuit is enhanced with respect to electric noise.